Novel SnO2@ZnO hierarchical nanostructures for highly sensitive and selective NO2 gas sensing

Zhiyong Zhang*, Manzhang Xu, Lin Liu, Xiongfei Ruan, Junfeng Yan, Wu Zhao, Jiangni Yun, Yingnan Wang, Sujie Qin, Ting Zhang

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

160 Citations (Scopus)


The novel brush-like (B–) SnO2@ZnO hierarchical nanostructures (HNSs) are successfully synthesized by using a simple two–step hydrothermal method. The SnO2 nanowires (NWs) grow epitaxially on the non–polarized plane of ZnO nanorods (NRs) with a six–fold symmetry. The heterogeneous nucleation–growth processes of SnO2 and ZnO are discussed in detail based on the dissolution–recrystallization mechanism, growth kinetics and Ostwald ripening. The excellent sensing performances of B–SnO2@ZnO HNSs for NO2 gas sensor are developed, including good selectivity, ultrasensitive, fast response, broad detection range and low detection limits. The detection range of the sensor is measured from 5 ppb to 10 ppm, and the detection limit of the sensor is 5 ppb at 150 °C. The response and recovery time which reach 90% of the final signal is less than 60 s, while retaining the low detection limit. The sensing mechanism is also discussed, and the unique structure of B–SnO2@ZnO is the dominating parameter for excellent sensing performances. The improved sensing performance of the HNSs also suggests the possibilities of other 1D materials combination for further sensing applications.

Original languageEnglish
Pages (from-to)714-727
Number of pages14
JournalSensors and Actuators, B: Chemical
Publication statusPublished - Mar 2018


  • Growth mechanism
  • Hierarchical nanostructures
  • NO sensing
  • Sensing mechanism
  • SnO@ZnO

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